Surface Mount Device identification Most of the following information was published in TELEVISION magazine. The list is not exhaustive and further submissions are welcome. Please DO NOT ASK ME if I know any other device markings. All the information I have is listed here. Another far more comprehensive list can be found here: http://www.marsport.demon.co.uk/smd/mainframe.htm As this is so much better and more up to date, I will not be updating the list below. Last updated October 14, 1999 1. PASSIVE DEVICES The following code marking systems are widely used for surface-mount resistors and capacitors. TRhe give the resistor value in Ohms and the capacitor value in Picofarads. With the three sysmbol code, the first two digits are the base figures and the third is the multiplier (number of zeros to add). Thus "270" = 27 Ohms (27R) or 27pF. "331" = 330R or 330pF, "472" = 4.7k (4k7) or 4.7nF (4n7F). "2R2" = 2.2Ohms and "2P2 = 2.2pF. The two-symbol code uses a letter to indicate the base figure in Ohms or pF, and the second digit to indicate the multiplier: A=1 B=1.1 C=1.2 D=1.3 E=1.5 F=1.6 G=1.8 H=2 J=2.2 K=2.4 a=2.5 b=3.5 d=4 e=4.5 f=5 m=6 n=7 t=8 y=9
Transcript
Surface Mount Device identificationMost of the following information was published in TELEVISION magazine.The list is not exhaustive and further submissions are welcome.Please DO NOT ASK ME if I know any other device markings.All the information I have is listed here.
Another far more comprehensive list can be found here:
http://www.marsport.demon.co.uk/smd/mainframe.htm
As this is so much better and more up to date, I will not be updating the list below.
Last updated October 14, 1999
1. PASSIVE DEVICES
The following code marking systems are widely used for surface-mount resistors and capacitors. TRhe give the resistor value in Ohms and the capacitor value in Picofarads.
With the three sysmbol code, the first two digits are the base figures and the third is the multiplier (number of zeros to add). Thus "270" = 27 Ohms (27R) or 27pF. "331" = 330R or 330pF, "472" = 4.7k (4k7) or 4.7nF (4n7F). "2R2" = 2.2Ohms and "2P2 = 2.2pF.
The two-symbol code uses a letter to indicate the base figure in Ohms or pF, and the second digit to indicate the multiplier:
Aluminium electrolytic SM capacitors may have a three-symbol code with numbers to indicate capacitance in uF (microfarads) and a letter to indicate the voltage rating. The letter code is as shown ----->
The position of the letter indicates the decimal point position in the capacitance value. Thus "F47"=0.47uF/25v.
C=6.3v
D=10vE=16vF=25vG=40vH=63v
2. SEMICONDUCTORS
Because of their small size, it's not possible to show types/ values on most surface-mounted components. The following tables show the code markings used to identify most common surface-mounted transistors and diodes. Note that the same code marking may be used for different devices, dependent on the device encapsulation (SOT-23,SOT-89 etc.).
Types in SOT-23,SOT-89 and SOT-143 encapsulations are marked as below. The actual type number and data code are shown on the packing. SOT-89 types usually have the type number marked in full on the encapsulation: the BZV49 series is an exception. Code markings followed by * apply to SOT-23 devices, those followed by + apply to SOT-89 devices and those by # to SOT-323 devices.
Some device markings may be followed by a lower case letter such as "p" for Philips. In European devices this is usually the manufacturer's initial. In Japanese (ROHM) types it may be the gain (hfe) marking. (ROHM types are listed after the American and European types but some are also included in the first list - just to confuse!)
European (Philips) Devices (other manufacturers as designated in brackets)
Most Japanese device encapsulation descriptions and sizes differ from European or American ones. The same code markings may be used with different encapsulations, so it is first necessary to identify the encapsulation by its size. The length is measured along the plastic body but the width across the narrow body direction includes the legs as well.
EM3 Pack L=1.6mm, W=1.6mmUMT/SC70 L=2mm, W=2.1mmSMT Pack L=2.9mm, W=2.9mmSOT23 L=2.9mm, W=2.9mmThere are also five and six-leg encapsulations.Some codes may be followed by a gain (hfe) marking.
